Considerations of dietary sodium/potassium/energy ratios of selected foods

Various electrolytes and energy intakes have been shown to contribute to the risk of hypertension and other cardiovascular diseases. Further, dietary sodium (Na) and potassium (K) balance are important in both nonpharmacologic and pharmacologic management of various cardiovascular states. Emphasis is also given to weight reduction and electrolyte balance. As an aid to food selection to enhance K intake and decrease Na intake, we have categorized foods according to their electrolyte density as related to caloric content. More than 100 individual food items were assigned to one of four categories. Ratios of individual Na, K, and energy content were calculated, based on USDA-generated food nutrient values. Category 1 includes foods that are low in Na, high in K and low in energy: fresh or frozen vegetable sources with vitamins A and C. Category 2 contains foods low in Na relative to high K and high energy: most fruit, starchy vegetables, nuts, milk and meat products, and chocolate. Category 3 includes foods high in Na that are also high in K in relation to low energy: vegetables (canned, frozen in butter sauce or au gratin), most cheeses, cured or frozen meats. Category 4 contains foods high in Na and low in K relative to high energy: bread, rice, luncheon meats, commercial cookies and pastries, and fast food entrees. Commercial cereals could be differentiated by the guidelines, with bran cereals in Category 1, shredded wheat products in Category 2, fruit-containing cereals in Category 3, and presweetened or instant cereals in Category 4. Identification of the ratio of Na and K to content of foods, compared with relative energy ratio, is useful in selecting foods that will help meet specific dietary criteria for management of essential hypertension and other cardiovascular-renal states, both in the adult and pediatric populations.